Generic drive devices and corresponding injection pumps are well known from the state of the art and have been successfully used in infusion therapy since long.
For example from WO 2011/039250 A1 a method for preventing inadvertent bolus administration regarding a manual feed movement of a slide means for an infusion syringe piston especially after replacing an infusion syringe on an infusion pump as well as the corresponding infusion pump are known. Apart from the slide means for sliding the infusion syringe piston, the infusion pump especially includes an infusion syringe seat for securing an infusion syringe, an advance comprising a two-part advancing spindle nut for driving the slide means as well as a means for blocking the manual infeed movement of the slide means. In this context, the advance excels by an advancing spindle and an advancing coupling for coupling or uncoupling the slide means with or from the advancing spindle, whereby in the uncoupled state of the coupling the slide means advantageously can be quickly manually fed to the infusion syringe piston of the newly inserted infusion syringe. Such quick manual feeding is of advantage especially in critical situations, when it is necessary to quickly administer a vital infusion to a patient. In order to be able to reduce the risk of a quite dangerous inadvertent bolus administration to the patient, however, the infusion pump is provided with a blocking means by which the manual infeed movement can be quickly inhibited, when the slide means has been manually fed sufficiently closely to the infusion syringe piston. In particular, the blocking means excels by a check thread shaft juxtaposed to the advancing spindle and including a threaded shaft nut non-detachably corresponding thereto and by a braking means for the check thread shaft. The threaded shaft nut is tightly connected to the slide means so that the manual feed movement immediately blocks, when the braking means blocks rotation of the check thread shaft. The blocking means is controlled by a signal means associated with the slide means comprising at least one sensor at the slide means which is adapted to detect an approach of the slide means to the infusion syringe piston, the braking means blocking the check thread shaft, when a certain approach of the infusion syringe piston to the slide means is reached or exceeded. Hereby inadvertent or critical abutting against the infusion syringe piston in the course of quick manual feed movement can be reliably prevented. The blocking means includes an electromagnetic brake electrically connected to the signal means for blocking the check thread shaft.